In this section, the samples describe a type 2.1 casual connection between two NCPs over a switched SDLC link. In this context, a casual connection occurs when you define the two VTAM-NCP combinations as type 2.1 peripheral nodes to each other.

In this configuration, VTAM® A02N is channel-attached to NCP A04 and VTAM A81N is channel-attached to NCP A31. There are two switched SDLC connections between NCP A04 and NCP A31. For a picture of this type of configuration, although with one switched connection instead of two, see Figure 1.

Each VTAM must define one NCP major node and two switched major nodes, one for each connection.

Switched major nodes A02CCN04 and A02CCN36 reside on VTAM A02N and define switched SDLC casual connections from NCP A04 to NCP A31. Switched major nodes A81CCN04 and A81CCN36 reside on VTAM A81N and define switched SDLC casual connections from NCP A31 to NCP A04.

Note that for a switched connection, when the type 2.1 peripheral node is a VTAM, the CPNAME operand must be used. The CPNAME operand specifies the control point name of the type 2.1 peripheral node.

The NCP major node definitions are in NCP type 2.1 switched SDLC casual connection. The switched major node definitions follow.